The subject matter herein relates generally to card edge connectors.
There are numerous protocols used to communicate information among digital devices. Various standards have been applied to permit connection of peripheral devices such as network interface cards, storage adaptors, graphics cards, and other devices to a computer motherboard. For example, card edge connectors, connected to the motherboard, receive circuit cards or peripheral expansion boards. The peripheral expansion boards are available in a variety of form factors. Some peripheral expansion boards feature small form factors applicable to space constrained applications, such as notebook computers. Some peripheral expansion board form factors are targeted at desktop computers where more space is available to accommodate a larger form factor. One protocol which has been developed for transporting computer bus protocols is the PCI-Express (PCIe) protocol. Other protocols exist.
The card edge connectors include a card edge slot that receives the peripheral expansion board. The card edge connector holds many contacts for interfacing with corresponding pads on the peripheral expansion board. Due to size constraints, and the desire for smaller and smaller connector footprints, the many contacts are arranged in close proximity within the connector and at the mother board interface. Having the contacts in such close proximity affects the electrical performance of the contacts. For example, interference from other contacts degrades the signals and diminishes the overall electrical performance of the connector. At higher data rates, the signal degradation is more problematic.
A need remains for a connector operable at high data rates with improved electrical performance.